Characterization of the size and position of electron–hole puddles at a graphene p–n junction

Abstract

The effect of an electron-hole puddle on the electrical transport when governed by snake states in a bipolar graphene structure is investigated. Using numerical simulations we show that information on the size and position of the electron-hole puddle can be obtained using the dependence of the conductance on magnetic field and electron density of the gated region. The presence of the scatterer disrupts snake state transport which alters the conduction pattern. We obtain a simple analytical formula that connects the position of the electron-hole puddle with features observed in the conductance. Size of the electron-hole puddle is estimated from the magnetic field and gate potential that maximizes the effect of the puddle on the electrical transport.

Valley Hall effect and nonlocal transport in strained graphene

“…The strain-induced VHE that we predict should be observable with fairly modest strain levels in hall bar devices. Furthermore, unlike recent work along similar lines, 1,3,4,24,25 which focuses on nanometersize devices and ballistic transport, our results apply to much larger and disordered devices in the micrometer scale, where conduction takes places in the diffusive regime. The latter are also potentially much more interesting from the application point of view.…”